Aspirator for administering medicine



Dec. 26, 1950 J. H. EMERSON 2,535,844

ASPIRATOR FOR ADMINISTERING MEDICINE Filed Au 1, 1946 I 722162241502"T157272 HZ/mersmz z 8 6 M J Attys Patented Dec. 26, 1950 UNITED STATESPATENT OFFICE ASPIRATOR FOR ADli/IINISTERING MEDICINE John H. Emerson,Cambridge, Mass.

Application August 1, 1946, Serial No. 687,586

(Cl. Mil-"195) 10 Claims. 1

This invention pertains to aspirators such as are employed in adminstering medical substances in spray form, for instance for inhalation bya patient, and in particular to an aspirator designed for use withmedicaments which are too expensive to waste. For example penicillin hasbeen found effective as an inha ant in the treatment of some forms ofasthma, but at the present price of penicillin it is not available tomany persons who would benefit from its use because of the wastefulmethods of administration.

It has heretofore been proposed to employ apparatus for this purposewherein the penicill n or other medical substance is atomized by a jetof oxygen and wherein the patient by the operation of a valve or ventlimits the actual atomization to the period of inhalation so that themedicine is not wasted during exhalation. While this prior apparatus isuseful, it is necessary for the patient to manipulate the control valveor vent. .This places a considerable burden upon a patient even thoughhe may be able to do so, and many patients are wholly unable to performthis operation. 7

The object of the present invention is to provide apparatus of the typeabove referred to wherein a l quid medicament is atomized by a jet ofcompressed gas, for example oxygen, and having provision for theautomatic limitation of the atomizing action to the period ofinhalation, thus relieving the patient of the necessity of manipulatingany control devices, and at the same time avoiding any waste of theexpensive medicine. Another object of the invention is to provide simpleatomizing apparatus for the intended purpose and such as may bemanufactured at a reasonable cost so as to make it generally available.Other and further objects and advantages of the invention will bepointed out i in the following more detailed description and byreference to the accompanying drawings wherein Fig. 1 is a diagrammaticelevation illustrating the novel apparatus;

Fig. 2 is an edge elevation, partly broken away and to larger scale,showing details of the control mechanism with the parts in the positionwhich they occupy during inhalation; and

Fig. 3 is a view similar to Fig. 2 but showing the position of the partsduring exhalation.

Referring to the drawings, the numeral designates a casing of anysuitable material, for instance a moulded plastic, glass or metal,delining a chamber 2, the lower part of which, in

the simple construction herein illustrated, constitutes a reservoir fora body 3 of the medicinal substance which is to be administered. Thecasing l is provided with a tubular branch 4 defining the deliverypassage 5. This branch 4 may be shaped to be held in the mouth of thepatient or alternatively it may be shaped tofit into one nostril or intoboth nostrils. The casing also has the tubular branch 6 providing thebreathing port I, this port being of a size sufli'; cient to admit thepassage of air in sufiicient quantity for breathing.

Within the chamber 2 there is arranged a jet nozzle 8 which is suppliedwith the medicinal substance from the body 3 by means of an elevat ngtube 9 supported by a rigid bracket It). The upper end of the elevatingtube is so arranged, relatively to the jet nozzle 8, that the aspiratingeffect of gas delivered from the jet nozzle lifts the medicinalsubstance to the nozzle tip so that the medicinal substance is atomizedby the jet of gas issuing from the nozzle. The

pressure motor l6 comprising a case I! which houses a very light andflexible diaphragm Hi. The case defines a chamber l9, at one side of thediaphragm, which communicates by means of a tube 2E3 with the chamber 2of the casing I. Since the chamber I9 of the pressure motor communicateswith the chamber 2 of the casing i the diaphragm is responsive topressure variations in the chamber 2. The right-hand side of thediaphragm is open to atmospheric pressure at all times.

The support I5 is provided with a discharge port/2! which is controlledby a movable valve head 22. As illustrated, this valve head is carriedby a lever 23 having an arm 23 which engages the central part of thediaphragm It; so that motion of the diaphragm causes the valve 22 to beseated or unseated.

Assuming that gas under pressure is being supplied through the tube I4to the tubular support l5 and is thus available for delivery to the jetnozzle 8, if the patient places the part 4 in his mouth and inhales, thepressure in chamber 2 is slightly reduced, and this reduction inpressure is communicated to the chamber I9, thus the liquid to thenozzle tip in response to the aspirating action of the issuing gas jet,valve means including a movable valve head operative alternatively todeliver gas to the nozzle or to vent the gas to the atmosphere and apressure motor including a movable diaphragm which moves in onedirection in response to exhalation pressure and in the other directionin response to inhalation pressure, and means so connecting thediaphragm and valve head that the valve head is actuated to vent the gasto the atmosphere, thereby to cease vaporization during periods ofexhalation.

9. Apparatus for use in administering a medicinal substance in atomizedform for inhalation by a patient, said apparatus comprising a vaporizingnozzle, and having provision, includ ing a constantly open, unobstructedconduit for supplying gas under pressure to said nozzle, said conduithaving a vent port intermediate its ends, and a movable valve headoperative at times to close said port, and automatic means responsive toexhalation pressure to open said valve thereby to vent the gas to theatmosphere at a point intermediate the ends of the conduit.

10. Apparatus for use in administering a medicinal substance in atomizedform, comprising means defining a chamber through which the patientinhales and exhales, the chamber having a constantly open aperture inits Wall of a size sufficient to pass air in the amount requisite forbreathing, but such that the pressure in the chamber decreases andincreases slightly in response to inhalation and exhalationrespectively, a nozzle arranged to discharge the atomized medicinalsubstance into the chamber, a constantly open unobstructed conduit forleading gas under pressure from the source of supply to the nozzle, andmeans responsive to exhalation pressure Within the chamber to vent thegas on its way from the supply to the nozzle to the outer atmosphere.

JOHN H. EMERSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,181,421 Fahr et a1. Nov. 28%,1939 FOREIGN PATENTS Number Country Date 500,789 Great Britain Feb. 151939

